United States
Department of
Agriculture
Forest Service
Technology &
Development
Program
7300–Facilities
August 2008
0873–2841–MTDC
Is My Building Sick?
A Manager’s Guide to Identifying and
Solving Indoor Air Quality Problems
Is My Building Sick?
A Manager’s Guide to Identifying and
Solving Indoor Air Quality Problems
Kathleen Snodgrass
Project Leader
Kristopher Kusano
Project Assistant
USDA Forest Service
Technology and Development Center
Missoula, MT
6E62F37 Air Quality Evaluation Guide for Managers
August 2008
The Forest Service, United States Department of Agriculture (USDA), has developed this
information for the guidance of its employees, its contractors, and its cooperating Federal
and State agencies, and is not responsible for the interpretation or use of this information
by anyone except its own employees. The use of trade, firm, or corporation names in this
document is for the information and convenience of the reader, and does not constitute
an endorsement by the Department of any product or service to the exclusion of others
that may be suitable.
Cover photo—A view of the reception desk in the
interpretive and reception area that was added
in 2004 to the 1950s-vintage McKenzie River
Ranger Station, Willamette National Forest, Pacific
Northwest Region. Both new and old buildings can
experience poor indoor air quality.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and
activities on the basis of race, color, national origin, age, disability, and where applicable,
sex, marital status, familial status, parental status, religion, sexual orientation, genetic
information, political beliefs, reprisal, or because all or part of an individual’s income is
derived from any public assistance program. (Not all prohibited bases apply to all programs.)
Persons with disabilities who require alternative means for communication of program
information (Braille, large print, audiotape, etc.) should contact USDA’s TARGET Center
at (202) 720-2600 (voice and TDD).
To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400
Independence Avenue, S.W., Washington, D.C. 20250-9410, or call (800) 795-3272 (voice)
or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.
Table of Contents
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Responsibilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Symptoms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Identifying the Causes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Fixing the Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Final Thoughts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Indoor Air Quality Problem Fact Sheet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Common Symptoms, Causes, and Solutions to Indoor Air Quality Problems. . . . . . . . . . . . . . . . . . . . . . 8
More Information About Indoor Air Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Acknowledgments
T
he authors would like to thank Forest Service employees Art Johnston, Mark McDonough, and Beverly Young for
reviewing this report and providing helpful suggestions. Thanks also to Forest Service employees Tom Cassell, Kate
Endersbe, Mike Godfrey (retired), Steve Oravetz, and Thad Schroeder for providing photos.
ii
Introduction
I
ndoor air quality has become a concern in the workplace
because poor air quality can harm the health, comfort,
well-being, and productivity of building occupants.
While most buildings don’t have severe indoor air
quality issues, even well-run buildings sometimes experience
episodes of poor air quality. The Occupational Safety and
Health Administration estimates that as many as a third of
American employees work in a building that has indoor air
quality issues.
Poor indoor air quality is usually not as easy to identify
or correct as a wobbly desk or a leaky faucet. Indoor air
quality is influenced by many factors inside and outside a
building that may change over time. Sometimes employees
think other factors that affect their health or comfort are
indoor air quality problems.
Although it may seem counterintuitive, the first step
to solving indoor air quality problems is not an air quality
test. This report will help building managers understand
the actions they can take to identify and correct the most
common sources of indoor air quality issues. Funds can be
used to fix problems rather than pay for expensive tests. This
report also explains when to get assistance from a specialist,
such as a facilities engineer or industrial hygienist.
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Responsibilities
A
ll employees have a responsibility to inform their
supervisor of any personal, physical, or mental
condition that could compromise the safety or
health of themselves or coworkers (Health and Safety Code
Handbook, Forest Service Handbook 6709-11, section
04.4). Employees need to let their supervisor know if they
experience symptoms as a result of indoor air quality issues.
Issues can’t be addressed if they are not identified.
First-line supervisors are responsible for identifying jobrelated hazards and eliminating potential causes of accidents
and injuries to the best of their ability. Most supervisors
can best protect their employees by reporting air quality
problems that don’t have obvious and immediate solutions to
their line officer rather than trying to solve the problem. Line
officers are responsible for the health, safety, and training of
employees. Line officers usually direct the facilities manager
to investigate and solve indoor air quality problems.
Be sure to let all of the building’s occupants know
when an indoor air quality issue or complaint is being
investigated. When you locate the source of a problem, let
occupants know what was found, and how and when it will
be fixed. Occupants who are well informed are more likely to
cooperate with an investigation and participate in a solution,
and they are less likely to file a grievance or complain to a
regulatory agency about the problem.
1
Symptoms
O
ften the first signs of an air quality problem are
employee complaints of symptoms such as:
• Eye, nose, and throat irritation
• Coughing and sneezing
• Headaches
• Fatigue
• Irritability
• Allergies and sinus congestion
• Dizziness
• Difficulty concentrating
• Shortness of breath
• Skin irritation
• Nausea
Of course, these symptoms are not always caused by
air quality problems; they can have other causes, including
minor illnesses such as the common cold, lack of sleep,
smoking, medications, or serious illnesses. Still, if building
occupants report these symptoms—especially if the
symptoms occur mainly when employees are in the building
or when several individuals are affected—their concerns
must be taken seriously.
Some individuals are more sensitive to air contaminants
than others. Sometimes only one or a few individuals in
a building suffer from symptoms, while other employees
don’t even notice a problem (figure 1). That doesn’t mean
that problems experienced by a few employees are “all in
their head” and can be ignored. A sensitive individual can
be the “canary in the coal mine,” exhibiting symptoms of a
problem that may subtly affect the productivity of most of
the workforce. On the other hand, sometimes nobody other
than the sensitive individuals will ever be affected. In either
case, it’s in everybody’s best interest to make sure indoor air
quality problems don’t harm employees.
You will often hear the terms “sick building syndrome”
and “building-related illness” when poor indoor air
quality is discussed. If 20 percent of the building’s regular
inhabitants experience related symptoms for more than 2
weeks, the problem is classified as sick building syndrome.
If the symptoms of the employees are long lasting and can
2
Figure 1—One of these Forest Service employees could experience
symptoms related to poor indoor air quality while the other could be
unaffected. Natural sensitivities and stress can make people more likely to
experience symptoms related to poor indoor air quality.
be clinically diagnosed, it is a building-related illness. If
you want to know more about sick building syndrome or
building-related illness, see the “More Information About
Indoor Air Quality” section at the end of this report.
Sometimes working conditions can cause symptoms that
employees blame on poor indoor air quality. Noise, too little
light, glare, too much or too little heat or humidity, vibration,
overcrowding, poor ergonomics, and job-related psychosocial
issues can produce symptoms similar to those associated
with poor indoor air quality. Those conditions can add stress
that may make people more likely to be affected by indoor
air quality issues. Problems related to working conditions
should be corrected, but are not addressed in this report.
Asbestos and radon are sometimes considered indoor
air quality issues. However, symptoms from asbestos and
radon usually don’t appear for many years after exposure, so
these contaminants usually will not produce symptoms that
lead to employee complaints about poor air quality. For more
information about asbestos in Forest Service buildings, see
the “Asbestos” section of the Facilities Toolbox (http://www.
fs.fed.us/eng/toolbox/haz/haz02.htm). For more information
about radon in Forest Service buildings, see the “Radon”
section of the Facilities Toolbox (http://www.fs.fed.us/eng/
toolbox/haz/haz05.htm).
Identifying the Causes
T
o cure indoor air quality problems, you need to know
what’s causing them. The causes of most air quality
problems can be identified by interviewing employees
and conducting a thorough inspection of the building.
Occupants’ symptoms can help you focus the search
for the cause of indoor air quality problems. For example, if
employees are complaining about a solvent smell, throat and
eye irritation, and headaches, you are probably looking for
a chemical being used nearby, a solvent spill, or something
that is offgassing chemicals (figure 2). Knowing where
and when the symptoms are experienced can provide clues
to the source of the problem. For example, the chemical
use, spill, or offgassing is probably occurring near the area
where employees experience the symptoms or somewhere
connected by air distribution. Inspecting those areas will
probably reveal the cause of the problem.
Once you have learned the locations that appear to be
affected and have an idea of the occupants’ symptoms, you
need to investigate the affected area. A small-scale drawing
of the building’s floor plan, such as a building evacuation
map, can be used to record your findings. The table of
“Common Symptoms, Causes, and Solutions to Indoor
Air Quality Problems” at the end of this report contains
information that can help you find the source of indoor
air quality problems. More comprehensive information
and tables are available in the “Diagnosing and Solving
Problems” section of the U.S. Environmental Protection
Agency’s “Indoor Air Quality Building Education and
Assessment Model (I-BEAM)” Web site at http://www.epa.
gov/iaq/largebldgs/i-beam/text/diagnosing.html.
Use common sense and investigate thoroughly. For
example, if occupants complain of a musty smell or have
symptoms consistent with mold, look for places where mold
might be growing. If the basement floor is wet and mold
has begun to grow on the floor joists (figure 3), look for
plumbing leaks. If you don’t find plumbing leaks, look for
ways that water could have entered the crawl space from
outside the building, such as improperly adjusted irrigation
sprinklers, slopes that funnel runoff to window wells,
downspout discharges against a foundation wall, blocked
foundation drains, and so forth.
Figure 2—New cabinets, such as those in this bunkhouse, are sometimes
the source of chemicals that offgas, contributing to poor indoor air quality
and possibly causing headaches or throat and eye irritation.
For smaller buildings, you often can pinpoint affected
areas and identify symptoms simply by walking through
the building and talking to occupants. In larger buildings,
relevant information can be difficult to collect and track. A
feedback form completed by building occupants can help
an investigator obtain information. The “Indoor Air Quality
Problem Fact Sheet” at the end of this report or another form
can be used to gather information. Feedback forms should be
completed by all building occupants, not just those who have
complained of air quality problems, to obtain a complete
picture of the problem.
Figure 3—The light and dark gray spots on these floor joists are mold that
could cause wheezing, skin rashes, eye irritation, or other symptoms.
3
Over half of all indoor air quality problems are caused
by inadequate ventilation. When buildings are properly
ventilated, contaminants are less likely to become concentrated
enough to affect people’s well-being. “Dilution is the solution
to pollution” is an old saying with a lot of truth to it.
If the source of an indoor air quality problem is not
evident, check the heating, ventilation, and air conditioning
(HVAC) system for any of the following problems:
• Air intakes are blocked.
»» Air return grills are covered inside the building.
»» Air intake vents outside the building are covered
or misadjusted.
»» Automatic dampers for air intake vents are not
functioning properly.
• The ventilation rate is inadequate for the number of
people in the space.
»» Appropriate ventilation rates are explained in
the American Society of Heating, Refrigerating,
and Air-Conditioning Engineers (ASHRAE)
standards 62.1 and 62.2.
»» The recommended ventilation rate is 20 cubic feet
per minute per person in most office areas.
»» You can learn more about ventilation standards
from the “More Information About Indoor Air
Quality” section at the end of this report.
»» Your facilities engineer can help you determine
whether the ventilation rate is adequate.
• Air filters have not been changed or cleaned recently
or are not the correct type.
• Air handlers and ducts are not clean.
4
• Fumes such as those from shop work, office
equipment, restrooms, or janitor’s supply rooms are
being pulled into the HVAC system through return air
ducts rather than being exhausted directly outdoors.
• Pollutants or irritants such as vehicle exhaust, pollen,
mold, or welding fumes are being sucked into the
building through the outside air intake or return air
grills for the HVAC system.
• Air pressure differences cause exhaust air or flue
gasses to be drawn back into the building.
• Slime or mold is growing inside a cooling tower, drip
pan trays, or ductwork.
• Accumulated deposits in boiler tubes, furnace flues,
or piping prevent the efficient flow of combustion air,
exhaust, or fuel.
Water is a common cause of air quality problems
because mold will grow anywhere there is moisture and food
(dead organic material such as fabric, dirt, particleboard,
or lumber). If there has been recent flooding (especially in
crawl spaces or other hidden areas), a leaky roof, or any other
accumulation of moisture inside the building for a week or
more, mold could be growing.
Objects inside your building could be offgassing
chemicals. Formaldehyde and other gasses are often given off
by new building materials, especially paint, glue, carpeting,
and furnishings. Areas where solvents, glues, chemicals,
or other hazardous materials are stored or used may not be
properly vented. A can of solvent or other volatile material
may have spilled.
If you can’t find the source of the problem, contact your
facilities engineer for assistance. Be sure to tell the facilities
engineer what you’ve already done and the possibilities
you have investigated. Your facilities engineer can conduct
a more thorough investigation of the building’s systems or
conduct simple air tests. Chemical smoke tests can detect
air movement that might indicate entry points of pollutants.
Carbon dioxide and relative humidity test results can indicate
potential problems. Your facilities engineer can also help you
find a good industrial hygienist, if you need one.
An industrial hygienist can test the air in your building
for hazardous substances. An experienced industrial
hygienist also should be able to offer suggestions about
where the pollutants may be originating and how they may
be getting to the affected areas. An industrial hygienist’s
services are expensive, so hire one only when the hygienist’s
expertise is likely to help solve your problem.
No affordable test can analyze all the substances in
the air. Even tests for individual substances or classes of
substances can be expensive. One national forest spent
$25,000 trying to determine the cause of symptoms affecting
two employees. The tests provided no insights into the
problem.
That’s why it’s important to do an investigation first—
you need to have a reasonably good idea of what you’re
looking for before spending money on testing. Also, since
most problems can be identified during an investigation,
air tests are usually unnecessary. If you do a thorough
investigation, you can usually spend your money solving
problems rather than testing air.
It doesn’t help just to know which pollutants are in the
air. Even knowing the concentrations of pollutants may not
help. Tests that can help solve problems include those that:
• Compare concentrations of pollutants in different
parts of the building and possibly the outdoors to help
pinpoint sources of pollutants.
• Check emissions from a particular piece of equipment
to determine whether the equipment is the source of
the problem.
• Determine the concentration of compounds or conditions
that identify a particular type of air quality problem.
»» Carbon dioxide concentrations higher than 1,000
parts per million indicate inadequate ventilation
of occupied areas.
»» Carbon monoxide averages higher than 9 parts
per million for 8 hours, or a 1-hour average higher
than 35 parts per million indicate the presence of
combustion gasses.
»» Relative humidity higher than 50 percent may
indicate inadequate ventilation, depending on
outdoor conditions and whether the building
has an air conditioning or dehumidification
system. Mold is more active when humidity and
temperatures are high.
Testing also can compare measured concentrations
to exposure standards or public health guidelines for
some specific pollutants. When deciding whether tests
and comparisons will help you solve an indoor air quality
problem, keep in mind that it is rare for these standards
and guidelines to be exceeded in a Forest Service building.
The exposure limits are established to avoid acute medical
problems in industrial settings. Much lower exposure levels
and milder symptoms are typical in office buildings with
poor indoor air quality. You can learn more about pollutant
guidelines and standards in the “More Information About
Indoor Air Quality” section at the end of this report.
5
Fixing the Problems
O
nce you know what’s causing an indoor air quality
problem, you can fix it. Most fixes are pretty
obvious—clean, repair, unblock, replace, switch
to a different product, and so forth. If you’re not sure what
to do, check the table of “Common Symptoms, Causes, and
Solutions to Indoor Air Quality Problems” at the end of
this report. The cure may be one or several of the suggested
solutions. More comprehensive information and tables are
available in the “Diagnosing and Solving Problems” section
of the U.S. Environmental Protection Agency’s “Indoor
Air Quality Building Education and Assessment Model
(I-BEAM)” Web site at http://www.epa.gov/iaq/largebldgs/ibeam/text/diagnosing.html.
Your facilities engineer can help you identify an
effective solution if one isn’t obvious. The facilities
engineer will probably begin by comparing the design or
original performance characteristics of the building and
its components to the current design and performance
characteristics.
Often, something has changed since the building
was constructed, and building systems must be modified
to accommodate the change. For instance, a new carport
may have been constructed near the outside air supply for
an office’s HVAC system (figure 4). Fumes from vehicles
warming up under the carport canopy on frigid mornings
could be drawn into the building’s air distribution system.
The solution, which would depend on many variables, could
be as expensive as relocating the air intake or carport, or as
inexpensive (but inconvenient) as instituting a policy that
vehicles must be moved away from the carport while idling.
One of the most common changes that can cause poor
indoor air quality is the addition of partitions, such as walls
or cubicles within a building. Added partitions often hinder
Figure 4—Vehicle exhaust could be drawn into a building’s HVAC system
if a carport is near the air intake. The air intake for this building is on the
roof to prevent vehicle exhaust from being drawn into the Nogales Ranger
Station of the Coronado National Forest in the Southwestern Region.
air circulation because they divide the space into small areas
that don’t have HVAC supply or return grills. The result can
be areas or rooms with stagnant air where pollutants can
concentrate. Occupants also may notice inadequate heating
or cooling. Correcting these problems may require elevating
cubicle dividers above the floor, cutting holes in doors or
walls to install louvered vents, adjusting ductwork, adding
fans or exhaust vents, or even replacing the whole HVAC
system.
In some situations, the most effective solution may be
to relocate affected individuals. For instance, if one or a few
people are affected adversely by a material that is needed to
protect other employees or to accomplish essential work, and
no acceptable substitute material is available, it may be better
to relocate persons who are being affected rather than to
eliminate use of the material.
Final Thoughts
T
he best way to cure indoor air problems is to
prevent them. It’s not possible to prevent all indoor
air quality problems. However, ensuring that each
building’s HVAC system is working properly and that
6
employees follow proper procedures when working with
hazardous substances can go a long way toward minimizing
indoor air quality problems.
Indoor Air Quality Problem Fact Sheet
To help identify and solve an indoor air quality problem, we need information from all building occupants.
Please complete this fact sheet—it will help us improve your work environment.
Your name:
Date:
Your work location:
Phone:
If you have recently experienced symptoms or discomfort related to the quality of the air in this building,
please describe them in this space:
Where are you when you experience
the symptoms or discomfort?
Where do you spend most of
your time in the building?
When did these symptoms or
discomfort start?
When are they generally worst?
Do they go away? If so, when?
Who else has these symptoms?
What events (weather, activities inside or outside the building, etc.) or conditions (temperature,
humidity, drafts, stagnant air, odors, etc.) tend to occur at about the same time as your symptoms?
Please describe in this space:
Is there anything else we should know about this problem? Please describe in this space:
Thanks for your help!
7
Common Symptoms, Causes, and Solutions to Indoor Air Quality Problems
Short-Term Symptoms
Eye, nose, and throat irritation,
headaches, pneumonia, fatigue,
bronchitis, flu-like symptoms,
dizziness, nausea, shortness of
breath
Impaired lung/respiratory
function, lung/respiratory
infections, ear infections in
children
Eye, nose, and throat irritation,
coughing, fatigue, rashes, and
allergic reactions
Eye, nose, and throat irritation
Headaches, irritation in mouth,
rash, excessive perspiration,
kidney damage
8
Possible Causes
Byproducts of combustion
(such as CO, CO2, NOx):
Unvented or poorly vented
kerosene and gas heaters, gas
appliances, wood- and gasburning fireplaces and stoves,
leaking chimneys and furnaces,
vehicle exhaust
What To Do
• Avoid use of unvented gas or kerosene space
heaters.
• Keep gas appliances and furnaces properly
adjusted.
• Install and use exhaust fans.
• Change HVAC filters regularly.
• Increase the supply of outside air.
• Don’t operate or idle vehicles near air intakes,
doors, or windows.
• Clean wood stoves and fireplace flues regularly;
check for proper draft; ensure adequate
combustion air supply.
Environmental tobacco smoke: • Prohibit smoking indoors.
Cigarettes, cigars, pipes
• Offer smoking cessation classes.
• Make sure that the smoking area is far away from
doors, windows, or air intakes.
Formaldehyde: Pressed wood
• Use products with lower emission rates of
products (hardwood, plywood,
formaldehyde.
particleboard, fiberboard) used
• Flush areas containing new materials with fresh
in buildings and furniture, ureaair for 2 weeks before occupying.
formaldehyde foam insulation,
• Keep humidity low.
permanent press textiles, some
• Increase ventilation.
glues, tobacco smoke, vehicle
• Avoid premature aging or baking of products.
exhaust, stoves, fireplaces
• See recommendations for combustion byproducts
and tobacco smoke above.
Pesticides: Garden and lawn
• Use alternate control methods when possible.
chemicals, poisons for pest
• Do not store in occupied areas.
control
• Follow manufacturer’s instructions.
• Increase ventilation.
Heavy metals: Paints, vehicle
• Vacuum and clean surfaces regularly.
exhaust, tobacco smoke, soil,
• Have experts remove deteriorated lead-based paint.
and dust
• Prohibit smoking.
• Eliminate entry paths for vehicle exhaust.
Short-Term Symptoms
Possible Causes
Eye, nose, and throat irritation,
headaches, loss of coordination,
nausea
Volatile organic compounds:
Paints, solvents, wood
preservatives, glue, aerosol
sprays, cleaners and
disinfectants, moth repellants,
air fresheners, hobby supplies,
dry-cleaned clothes, some
new furniture and carpets,
large format printers, blueprint
machines
Legionnaires’ disease,
humidifier fever, influenza, and
other airborne communicable
diseases
Bioaerosols: Humans, pets,
moist surfaces, humidifiers,
ventilation systems, drip pans,
cooling coils in air handling
units, plants, outside air
What To Do
• Read labels and material safety data sheets, follow
instructions and job hazard analyses.
• Use in well-ventilated areas that exhaust air to the
outside or use outdoors away from air intakes.
• Air out drycleaned clothes for about 6 hours
before bringing them into occupied areas.
• Clean spills promptly. Flush the area with fresh air.
• Air out new furniture, carpet, and new
construction 2 weeks before occupying.
• Purchase only low- or no-VOC (volatile organic
compound) paints, adhesives, and building
•
•
•
•
•
Nasal/sinus irritation or
congestion, dry hacking cough,
eye irritation, wheezing, skin
rashes or burning, shortness
of breath, increased asthma
symptoms, headaches
(symptoms vary)
Sneezing, increased asthma
symptoms, nasal congestion, eye
irritation
Mold: On building surfaces,
inside walls, ceilings, or floors;
potting soil or containers for
indoor plants
•
Common allergens: Dust, soot,
pollen, etc.
•
•
•
•
•
•
•
•
products for maintenance and repairs.
Remove the source.
Maintain cleanliness of HVAC and humidification
equipment, including drip pans and cooling tower
trays.
Use an air conditioner or dehumidifier to reduce
humidity.
Change HVAC filters regularly.
Install more effective HVAC filters—check the
HVAC manual.
Remove the source of moisture (plumbing or
structure leaks, condensation, trapped moisture).
Increase ventilation rate.
Clean impermeable surfaces.
Replace materials penetrated by mold.
Use an air conditioner or dehumidifier to reduce
humidity.
Change HVAC filters regularly.
Install more effective HVAC filters—check HVAC
manual.
Keep indoor surfaces clean.
Keep windows and doors closed when allergens
are present outdoors.
SOURCE: Adapted from U.S. Environmental Protection Agency and Consumer Product Safety Commission publications.
9
More Information About Indoor Air Quality
General Information
Hazardous Materials in Buildings
Aerias: Air Quality Sciences, Indoor Air Quality Resource
Center
• “Building-related illnesses” at http://www.aerias.org/
DesktopModules/ArticleDetail.aspx?articleId=16
U.S. Environmental Protection Agency (EPA)
• “Indoor Air Quality” Web page at http://www.epa.
gov/iaq/
»» “Indoor Air Facts No. 4: Sick Building Syndrome”
at http://www.epa.gov/iaq/pubs/sbs.html
• “Building Air Quality: A Guide for Building Owners
and Facility Managers” at http://www.epa.gov/iaq/
largebldgs/baqtoc.html
• “Indoor Air Quality Building Education and
Assessment Model (I-BEAM)” at http://www.epa.gov/
iaq/largebldgs/i-beam/
»» “Diagnosing and solving problems” I-BEAM text
module at http://www.epa.gov/iaq/largebldgs/ibeam/text/diagnosing.html
U.S. Department of Labor, Occupational Safety and
Health Administration (OSHA)
• “Indoor Air Quality Investigation,” section III,
chapter 2, in OSHA Technical Manual at http://www.
osha.gov/dts/osta/otm/otm_iii/otm_iii_2.html
Missoula Technology and Development Center Facilities
Toolbox
• “Hazardous Substances in Buildings” at http://www.
fs.fed.us/eng/toolbox/haz/
Mold
Exposure Limits
American Conference of Governmental Industrial Hygienists
• 2008 threshold limit values (TLVs) and biological
exposure indices (BEIs) at http://www.acgih.org/store/
ProductDetail.cfm?id=1975
U.S. Environmental Protection Agency (EPA)
• National ambient air quality standards at http://www.
epa.gov/air/criteria.html
Health Canada
• Exposure guidelines for residential indoor air quality
at http://www.hc-sc.gc.ca/ewh-semt/pubs/air/
exposure-exposition/index-eng.php
National Institute for Occupational Safety and Health
(NIOSH)
• “NIOSH Pocket Guide to Chemical Hazards” at
http://www.cdc.gov/niosh/npg/
U.S. Department of Labor, Occupational Safety and
Health Administration (OSHA)
• Table Z–1: Limits for Air Contaminants—1910.1000
at http://www.osha.gov/pls/oshaweb/owadisp.show_
document?p_table=STANDARDS&p_id=9992
World Health Organization
• Air quality guidelines: global update 2005 at http://
www.who.int/phe/health_topics/outdoorair_aqg/en/
Missoula Technology and Development Center Facilities
Toolbox
• “Hazardous Substances in Buildings: Mold” at http://
www.fs.fed.us/eng/toolbox/haz/haz04.htm
New York City Department of Health and Mental Hygiene
• “Guidelines on Assessment and Remediation of Fungi Ventilation Standards
in Indoor Environments” at http://home2.nyc.gov/
American National Standards Institute (ANSI)
html/doh/html/epi/moldrpt1.shtml
• Standard 62.1 “Ventilation for Acceptable Indoor Air
U.S. Department of Labor, Occupational Safety and
Quality” at http://webstore.ansi.org/RecordDetail.asp
Health Administration (OSHA)
x?sku=ANSI%2fASHRAE+62.1-2007
• “A Brief Guide to Mold in the Workplace” at http://
• Standard 62.2 “Ventilation and Acceptable Indoor Air
www.osha.gov/dts/shib/shib101003.html
Quality in Low-Rise Residential Buildings” at http://
webstore.ansi.org/RecordDetail.aspx?sku=ANSI%2fA
SHRAE+62.2-2007
10
About the Authors
Kathleen Snodgrass came to MTDC as a project leader in 2001. She graduated from Washington State University
in 1974 with a bachelor of science degree in architectural studies, then worked about 10 years in highway design and
construction for the Idaho Division of Highways. She began her Forest Service career in 1984. Snodgrass worked in facilities,
landscape architecture, land line, and general engineering on the Nez Perce National Forest for 10 years and was the forest’s
facilities architect for about 7 years before coming to MTDC.
Kristofer Kusano is a mechanical engineering student at Virginia Polytechnic Institute and State University (Virginia
Tech) who worked at MTDC as a summer intern during 2007. Before working at MTDC, Kusano worked for the Forest
Service’s Washington Office Engineering Staff as a student assistant.
Library Card
Snodgrass, Kathleen; Kusano, Kristofer. 2008. Is my building sick? A manager’s guide to identifying and solving
indoor air quality problems. Tech. Rep. 0873–2841–MTDC. Missoula, MT: U.S. Department of Agriculture Forest Service,
Missoula Technology and Development Center. 10 p.
Indoor air quality problems can harm the health, comfort, well-being, and productivity of a building’s occupants. This
report helps building managers locate and correct common sources of indoor air quality problems. It also explains when to
get assistance from a specialist, such as a facilities engineer or industrial hygienist.
Keywords: facilities, heating, how to, HVAC, illnesses, industrial hygienists, inspections, molds, offgassing, offices,
pollutants, productivity, safety at work, symptoms, syndromes, ventilation
Additional single copies of this document may be ordered
from:
USDA Forest Service
Missoula Technology and Development Center
5785 Hwy. 10 West
Missoula, MT 59808–9361
Phone: 406–329–3978
Fax: 406–329–3719
E-mail: wo_mtdc_pubs@fs.fed.us
Electronic copies of MTDC’s documents are available on
the Internet at:
http://www.fs.fed.us/eng/t-d.php
For additional information about indoor air quality,
contact Kathie Snodgrass at MTDC:
Phone: 406–329–3922
Fax: 406–329–3719
E-mail: ksnodgrass@fs.fed.us
Forest Service and Bureau of Land Management
employees can search a more complete collection of
MTDC’s documents, CDs, DVDs, and videos on their
internal computer networks at:
http://fsweb.mtdc.wo.fs.fed.us/search/